agentmail

agentmail is a skill for Claude Code from sinhoneyy/master-skills. It costs 31 tokens per session (2,260 once invoked), scanned A, original, no licence file.

Email infrastructure for AI agents through the AgentMail API. It supports agent email accounts, messages, webhooks, and usage balance management.

In plain words
What is it for?
Use it to create email accounts, send and receive messages, manage webhooks, and check AgentMail usage balance.
Why use it?
It handles the email-related setup an agent needs instead of requiring a separate system for each operation. Webhooks can notify an application about email events.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin.

Part of the master-skills-ai-agent-builder plugin — 195 skills, 1 plugin shipped together

Good fit Use it to create email accounts, send and receive messages, manage webhooks, and check AgentMail usage balance.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/sinhoneyy/master-skills/agentmail
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add sinhoneyy/master-skills --skill agentmail
Clone the repo
git clone --depth 1 https://github.com/sinhoneyy/master-skills

Made for: Claude Code.

Or install master-skills-ai-agent-builder, the plugin that ships this one along with the rest of its 195 skills, 1 plugin.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for agentmail

README.md
[![agentmods](https://agentmods.dev/badge/skills/sinhoneyy/master-skills/agentmail/github.svg)](https://agentmods.dev/skills/sinhoneyy/master-skills/agentmail)
Your own site
<a href="https://agentmods.dev/skills/sinhoneyy/master-skills/agentmail"><img src="https://agentmods.dev/badge/skills/sinhoneyy/master-skills/agentmail/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for agentmail

Your own site · 80×15
<a href="https://agentmods.dev/skills/sinhoneyy/master-skills/agentmail"><img src="https://agentmods.dev/badge/skills/sinhoneyy/master-skills/agentmail.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 31 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,260 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00031 $0.02260
Opus 5 $0.00015 $0.01130
Sonnet 5 $0.00006 $0.00452
Haiku 4.5 $0.00003 $0.00226

Measured 9d ago against content hash a68e8fc0b2b0, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

agentmail scanned grade A with 1 finding against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 9d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -X POST https://api.theagentmail.net/v1/accounts \
plugins/master-skills-ai-agent-builder/skills/agentmail/SKILL.md · 258 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 9d ago First seen · 258 lines · 31 tokens per session scan A a68e8fc0b2b0

Subscribe to this mod's changes

agentmail is a skill published in the GitHub repository sinhoneyy/master-skills (11 stars, last pushed 3d ago), with no licence file. It adds 31 tokens to every session and 2,260 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.